1. Field of the Invention
This invention relates to an artificial Christmas tree having an improved branch moving mechanism.
2. Description of the Prior Art
In some respects the present invention is an improvement over U.S. Pat. No. 3,900,637 entitled "Collapsible Christmas Tree Apparatus" and issued on Aug. 19, 1975 to Charles F. Byrd and William Dailey. The Byrd et al device includes an outer tubular member and an inner rod means which are adapted to impinge upon one end of a plurality of rotatable branches. There do, however, appear to be some practical problems involved with that disclosed design. One of the problems is that the design requires special pinning and welding in order to allow the limbs to rotate in a satisfactory manner. That kind of structure can be expensive to produce. Additionally, the design requires a plurality of spacers which are adapted to impinge upon the free end of the rotatable branches. The production and alignment of a rod having such tabs poses some difficult manufacturing problems. Finally, the effective lever length of the base end of the tree limb is slightly less than one-half of the diameter of the outer trunk. Therefore, the leverage end of the branches is very small relative to the length of the limbs themselves. Accordingly, it may take a considerable effort in order to erect and collapse the apparatus. The following possibly relevant references were cited during the prosecution of U.S. Pat. No. 3,900,637: U.S. Pat. No. 1,590,220; U.S. Pat. No. 3,159,523; and U.S. Pat. No. 3,465,139.
There are several other types of artificial trees that are known to those of ordinary skill in the art. Wedden, U.S. Pat. No. 2,708,324; Osswald et al, U.S. Pat. No. 3,030,720 and Hermanson, U.S. Pat. No. 3,639,196, all disclose collapsible artificial christmas trees having branches which rotate upwardly so as to reduce the bulk of the tree for storage purposes. Similarly, Hutton, U.S. Pat. No. 2,988,837; Scherotto, U.S. Pat. No. 3,020,660 and Blake, U.S. Pat. No. 3,176,123, disclose artificial trees which may be readily erected and collapsed through the use of expanding or collapsing elements.
In contrast to collapsible artificial trees, there are also a number of artificial shrubs and the like which incorporate the use of plug-in branches. Trees of this sort, are disclosed in the patents to Circelli, U.S. Pat. No. 3,746,600 and Strony, U.S. Pat. No. 3,746,601. Circelli is of particular interest in that it discloses an artificial shrub in which the branches are plugged into hinged or rotatable sockets. In this fashion, the tube or other cylindrical container may be slipped around the Christmas Tree which causes the branches to rotate upward, thereby reducing the width of the tree and increasing the ease with which the tree may be stored. Finally, there is also the type of artificial tree which is not truly collapsible, but instead may be knocked down or set up as a construction project. For example, see Carlson, U.S. Pat. No. 3,031,785.
One of the major problems with prior art artificial trees is that they are relatively difficult to erect. In addition, many of the prior art trees are not sturdy enough to take normal abuse. Frequently a tree that is relatively easy to erect is often a weak structure. Conversely, the stronger artificial Christmas Trees tend to be difficult to erect. Accordingly, the present invention fills a clear need by providing an artificial tree which is relatively easy to construct and relatively sturdy in its erected state.
From a mechanical point of view there is some similarity between collapsible trees and the mechanisms which are associated with umbrellas or clothes line drying apparatus. For examples of prior art relative to those apparatus, see for example, Beegle, U.S. Pat. No. 1,075,395; Place et al, U.S. Pat. No. 2,269,317; Alexiou, U.S. Pat. No. 3,038,690; and Gray, U.S. Pat. No. 3,069,021; O'Neil, U.S. Pat. No. 3,091,249; Raynor, U.S. Pat. No. 3,163,297 and Nugent, U.S. Pat. No. 3,464,664.